Much of the art bequeathed to us from the ancient Mediterranean world is in the form of mosaics.

"Mosaics are among the most durable forms of decorative art to have survived from antiquity," writes Katherine M. D. Dunbabin in her Mosaics of the Greek and Roman World. "Pavements of this type have been found by the hundred thousand in buildings of the Roman period from northern Britain to Libya, from the Atlantic coast to the Syrian desert."

Preserving this vast heritage, which provides a window into life in the distant past, is a considerable conservation challenge. Roman mosaics typically served as pavements in structures that long ago fell into ruin. Subsequent excavations have left many mosaics exposed to the elements in a way never intended, and the result has been their deterioration. Early excavators frequently removed mosaics, which may have preserved the mosaics themselves, but in the process they deprived sites of significant elements that were important for an understanding of their architectural and historic character.

Today there is greater recognition of the importance of preserving in situ the archaeological elements of a site, and mosaics are more likely to be left in their original locations. To effectively conserve and maintain mosaics in situ requires an understanding of the causes that lead to their deterioration, the development of methods to reduce the impact of those forces, and the training of professionals and technicians to carry out those methods.

With all this in mind, the Getty Conservation Institute began a project in the late 1990s to address a number of important issues related to the conservation and management of ancient mosaic pavements in situ. Focused on the Mediterranean region, the project builds upon previous GCI activities related to the conservation of mosaics. These included coorganizing a 1995 conference on the conservation of Mediterranean archaeological sites and cosponsorship of the 1996 conference of the International Committee for the Conservation of Mosaics, held in Nicosia, Cyprus.

The aim of the current project is to improve the conservation and management of mosaics in the Mediterranean area. One component of the project is research and testing that can contribute to a better understanding of the causes of deterioration of mosaics in situ and to the development of methods and approaches for their conservation—which include stabilization treatments and ongoing maintenance (i.e., regular monitoring, protective measures, and additional stabilization interventions when required).

The other focus of the project is improving the skills of technicians and professionals in the areas of maintenance, conservation, and management of sites with mosaics. Recently the GCI has been providing training in mosaic maintenance for conservation technicians in a country where a substantial number of Roman mosaics have been found.

View from the central restored garden of the Maison de la Cascade at the Roman site of Utica in Tunisia. The view is north toward the reconstructed main doorway. Excavation of this large house during the 1940s to 1960s uncovered numerous figurative and geometric mosaics. In a room off the peristyle, trainees carry out maintenance operations on the mosaic pavements. Photo: Richard Ross.

Tunisian Mosaics

The areas of North Africa along the Mediterranean that were once part of the Roman world are abundant in preserved mosaics—particularly in modern Tunisia. French archaeologist Henri Lavagne, a mosaics expert, has described the mosaics of the region as unquestionably the most inventive of those produced in the Roman provinces.

To preserve these mosaics, those responsible for excavations have, in the past, followed a policy of detaching mainly the valued figurative mosaics from their original locations and installing or storing them in a museum environment. Other detached mosaics, considered of lesser value (such as those with simple geometric designs), were frequently lifted and relaid in situ. While the value lost by removing mosaics from their architectural context is now acknowledged and while detaching is no longer common practice, conserving the mosaics in situ presents a formidable task.

In 1998, as part of the GCI's project on in situ mosaic conservation, the GCI and Tunisia's Institut National du Patrimoine (INP) initiated a program to save this immensely rich heritage from further deterioration. In that year, the GCI began to provide training for INP staff who would specialize in in situ mosaic maintenance.

In 2001, the GCI continued training in conservation of mosaics in situ with a program that involved most of the Tunisian technicians who participated in the 1998 course. As with the 1998 campaigns, this more recent program provided practical training to help the conservation technicians address the basic maintenance and stabilization needs of in situ archaeological mosaics. The trainees will eventually become an important part of a national strategy to safeguard Tunisia's archaeological heritage by creating maintenance teams based at sites in different regions of the country.

"We have thousands of mosaics," says Aïcha Ben Abed, head of research for the INP. "We have to try to bring the techniques of in situ mosaic conservation into our reality. That means using the technicians we have already—some with a good educational background, some with little education—and introducing them to these techniques."

The hands-on training initiative was carried out at the site of Utica, which 2,000 years ago had been a port city (today the coastline is approximately 10 kilometers away). Excavations undertaken at Utica between 1940 and 1960 revealed numerous and intricate Roman floor mosaics created between the first and fifth centuries. The INP-GCI training campaigns were conducted on mosaics that are part of the remains of a Roman house—the Maison de la Cascade—that dates from the first to the third century. This house includes geometric marble pavements and ceramic pavements, as well as mosaics. The polychrome mosaic for which the house was named was originally the decoration for a fountain and basin; the mosaic depicts a boat with fishermen casting their nets into a sea filled with a wide variety of fish.

The Training Campaigns

The principal aim of the 2001 Tunisian training, which involved nine employees of the INP, was to provide a methodology that would guide the work of the technicians in the future. The methodology includes three consecutive phases: study, maintenance planning, and implementation. The study phase involves documenting and assessing the condition of a mosaic. The second phase includes determining the type, extent, and urgency of the maintenance operations, as well as the personnel, materials, and time required, based on the condition assessment. The third phase involves carrying out and recording maintenance interventions.

Graphic recording of mortar repair treatments. Trainees use previously prepared drawings or photographs of the pavement to document different types of treatments. The recording becomes part of a documentation file for the mosaic which provides the basis for ongoing monitoring of the mosaic's condition and for planning of future interventions, as required, to prevent further damage and loss. Photo: Richard Ross.

The methodology taught to the trainees requires that during the above phases, conservation technicians complete written forms that become the core of the documentation file for each mosaic, along with graphic and photographic documentation. That file provides the basis for planning maintenance interventions and the frequency of future monitoring, and it is updated each time maintenance work is carried out.

The training activities were divided into three campaigns. Between campaigns, the technicians had the opportunity to gain additional practical experience on their own, which was later reviewed together with the instructors.

Assessment of the condition of a mosaic after reburial. Different materials and techniques used for reburial of mosaics were introduced during the training. Here, the effectiveness of a temporary protective covering of sand is evaluated after three years. Photo: Richard Ross.

The first campaign was devoted to learning and practicing written, graphic, and photographic documentation techniques in order to gain an understanding of the present situation by recording current conditions (including previous interventions) and then later recording maintenance treatments on the mosaics. The second and third campaigns were dedicated to hands-on, maintenance implementation. They included training on how to select the appropriate lime-based mortars for the various types of stabilization and repair treatments; when and how to carry out specific maintenance interventions, such as removal of vegetation, cleaning, and mortar repairs; and how to carry out ongoing monitoring of the mosaics and how to keep a maintenance file for each mosaic.

To support the learning in the classroom and on-site instruction, the GCI prepared sets of didactic and reference materials for the technicians. In addition, the technicians were equipped with tool kits and other practical job aids that will assist them in future work. The tool kits contained basic equipment for treatment activities, such as spatulas, sponges, brushes, dental tools, and scalpels.

As the job profile of a mosaic maintenance technician does not yet exist but rests somewhere between that of a conservator and a worker, these training activities must be considered experimental, and their success can be determined only with time. However, in a country that lacks many trained conservators, this type of technical worker—operating under the supervision of a site director but with a certain degree of autonomy regarding work methods and materials—presents the best possibility for carrying out the regular monitoring and routine interventions of maintenance that are necessary to prevent the loss of in situ mosaics.

Trainees and instructors performing cleaning and stabilization treatments. Stabilization work utilizes different lime mortar mixes to reset and fill gaps between the individual elements of two different types of Roman pavements—opus tesselatum (foreground) and opus sectile (center). Photo: Richard Ross.

Aïcha Ben Abed of INP believes that while this training approach is new to Tunisia, "the results that we can see are more than positive, more than encouraging." She observes a greater awareness among the technicians for the value of the mosaic itself, as well as the development of a new way of thinking about and handling the mosaics. Unexpectedly, over the course of the training, the group coalesced into a team. "They work together, they discuss together, they make decisions together. The big decisions are group decisions. That is a change."

A fourth and final training campaign for this group of technicians is planned for late spring 2002. In the fall, the GCI and the INP will begin another series of campaigns at the Roman and Byzantine site of Mactaris, with a new group of trainees primarily from the central region of the country. The continuing training activities are part of a developing strategy to create regional teams of maintenance technicians in order to respond to the great need for regular care of mosaics at numerous sites throughout Tunisia.

In addition, to complement the training initiative for mosaic conservation technicians and to strengthen the institutional framework and support for their work, the GCI and the INP are developing together workshops in site management planning for directors of archaeological sites and for other INP staff. This initiative will give site managers, archaeologists, and mosaic conservation technicians an opportunity to interact and to develop a mutual understanding of the technical and administrative means required to prevent the gradual loss of in situ mosaics.

Thomas Roby is a senior project specialist with the GCI and is the Institute's manager for the mosaics training program in Tunisia. Jeffrey Levin is editor of Conservation, The GCI Newsletter.